Largest Green Roof in the State Installed in Escambia County

Carrie T. Stevenson
Coastal Sustainability Agent
Escambia County Extension
ctsteven@ufl.edu

While the flat tops of most commercial buildings in Pensacola are hot, dry deserts of gravel and asphalt, the roof of Escambia County’s new “One-Stop” facility is awash in color and the frequent host to butterflies, bees, and dragonflies. Now the site of the largest green roof in Florida (over 30,000 sq. ft), the recently completed structure houses the county’s engineering, environmental, and building permit staff, and serves as a single stop for those applying for development and building permits from the county.  Complementing the green roof, the building and grounds also include pervious pavement, Florida-friendly landscaping, drip irrigation, significant day lighting, and water-saving plumbing fixtures. LEED certification for the facility is pending. Construction was funded partially with grant money from the Department of Environmental Protection’s TMDL Urban BMP Research and Demonstration program, and is the final of three green roof projects funded by DEP around the state.  For more information on the grants, visit www.dep.state.fl.us/water/watersheds/tmdl_grant.htm

A walkway around the clerestory provides good views of the the Indian blanketflower and sand cordgrass planted nearby. Photo Credits: Carrie T. Stevenson, IFAS Extension

During the design phase, Beth Bolles (Horticulture) and I accepted a request from county staff to help design the landscape for both the roof and surrounding grounds.  We sought input from horticulture specialists and looked at the designs of other green roofs around the state, and settled on a mixture of native, sun-loving, drought-tolerant groundcovers, grasses, and shrubs.  Knowing the conditions atop a roof would be relatively similar to those at the beach and maritime forests, we chose dune sunflower (Helianthus debilis), rosemary (Rosmarinus officinalis), and sand cordgrass (Spartina bakeri).  We also selected the more colorful Indian blanketflower (Gaillardia pulchella) and three tough but attractive groundcovers, powderpuff mimosa (Mimosa strigillosa), Stokes' aster (Stokesia laevis), and perennial peanut (Arachis glabrata).  The roof plantings are nearly complete and are rooted in a specialized growth media designed by Dr. Martin Wanielista, P.E., from the University of Central Florida.  The roof will be open to the public for tours, enabling visitors to see the roof layout up close and hopefully incorporate similar features into future development projects.

Native trees, drought-tolerant groundcovers, and drip irrigation are installed near the pervious parking lot of the new One-Stop facility. Photo Credits: Carrie T. Stevenson, IFAS Extension

The building will serve as a model of low impact development for northwest Florida, and a grand opening is scheduled for mid-November.